Our cosmic home—the Milky Way galaxy—continuously gives birth to new stars: on average, a couple of stars such as our own Sun are formed every year. These new stars form from the interstellar gas that is an indivisible component of the Milky Way. If a large-enough amount of this gas is located in a small-enough space, the gravity of the gas causes a gravitational collapse, followed by a formation of a new star. Exactly how does this process proceed is not yet well known. Specifically, it remains unknown how the different physical processes—such as gravity and turbulence—set the rate and efficiency with which the new stars form. As a result, our comprehensive understanding of how galaxies like Milky Way build up their stellar content remains lacking.
Overall, the question of “How do the stars form?” is linked to the fundamental question of our own origins in the Universe. Exploring and understanding such a topic has its main societal value in enabling and promoting critical, fact-based thinking and deep understanding of our own natural environment. On a more practical level, the study of the topic requires methods and technologies highly relevant in the modern society, for example, in the fields of data science, computer science, and engineering. Thus, the question “How do the stars form?” interfaces with the society by being a motivating question by its own right, by providing a route to develop skills that are in high demand in today’s society, and by providing a unique, curiosity-driven perspective to complex problem-solving.
The PROMISE project addresses fundamental open questions related to how the star formation process proceeds in the interstellar gas. The foremost goal of the project is to accurately map how the gas is distributed in a large number of star-forming gas clouds in the Milky Way. The exact distribution of gas determines its energetics, and from therein, where exactly the new stars can form. The PROMISE project focuses on exploiting novel and innovative observational techniques to map the gas distribution in thousands of gas clouds in the Milky Way in a detail that has not been available before. This enables PROMISE to make a step forward in understanding how the interstellar gas is distributed and how it is transformed into new stars in the Milky Way. The project was concluded successfully, resulting in the production of the ‘PROMISE galactic plane survey’ and several scientific results advancing our understanding of how new stars form in the Milky Way.
